topic Re: Powering OpenSDA circuit without USB connection in Kinetis Microcontrollers

Powering OpenSDA circuit without USB connection

gordonjess — Fri, 21 Feb 2014 13:20:23 GMT

Has anyone had any success powering the OpenSDA circuit on the FRDM-KL25Z without a USB connection, or perhaps advise me to the best way this can be achieved? I have an Ciseco URF wireless serial interface that I want to use to communicate data from the OpenSDA mini usb connector wirelessly to a laptop, for data logging. I would also like to keep the wired functionality so I can continue to program the board from USB. Thanks in advance

Re: Powering OpenSDA circuit without USB connection

Paul_Tian — Wed, 26 Feb 2014 06:55:19 GMT

Hi, Gordon

For your question1: I think the best way is connect power to pin1 of U1 on freedom board.

For your question2: I think it is impossible. Because mini usb uses usb communication interface but URF uses UART communication interface. So you cannot connect your URF to mini-usb directly,

Hope my reply can help you. Thanks.

Best Regards

Paul

Re: Powering OpenSDA circuit without USB connection

gordonjess — Wed, 26 Feb 2014 11:12:49 GMT

Hi Paul,

Thanks for your reply.

I have look at the schematics for the FRDM KL25Z and Pin 1 of U1 seems to be the ground connection for the voltage regulator. Are you looking at the same schematic? Also, the URF Module I was talking about does support USB communication, and I am able to connect it using a USB A to USB mini-B adapter.

Thanks,

Gordon

Re: Powering OpenSDA circuit without USB connection

Paul_Tian — Tue, 04 Mar 2014 03:07:10 GMT

Hi, Gordon

For question1: It should be pin3 not pin1.

For question2: OK. If your URF module can support USB function. I think it is possible. You only need to change the interface connection.

Hope my reply can help you.

Best Regards

Paul